Pressure indicator for pneumatic tires



Oct. 13, 1953 L. D. LOGGINS 2,655,571 PRESSURE INDICATOR FOR PNEUMATICTIRES Filed May 19, 1950 3 Sheets-Sheet l JNVENTOR. 41mm MIA/(AN low/usOct 13, I953 L. D. LOGGINS 2,655,571

PRESSURE INDICATOR FOR PNEUMATIC TIRES Filed May 19, 1950 3 Sheets-Sheet2 IN V EN TOR. ZUIIP/T/N MCMlW'G/NS ATTDRVEI' Oct. 13, 1953 L, D.LOGGINS 2,655,571 PRESSURE INDICATOR FOR PNEUMATIC TIRES Filed May 19,1950 5 Sheets-Sheet 3 A'rfollwsr Patented Oct. 13, 1953 UNITED STATESPAT ENT OFF I CE PRESSURE'INDICATOR FOR PNEUMATIC TIRESLumpkinLDJLoggins, Commerce, Ga. Application Mayl'9,1950,'Serial'No.'162,'880 .1 Claim. (01. ZOO-61.25)

The present invention relates to a pressure indicator :-'for v:pneumatictires and it consists in the combinations, constructions .andarrangements :of ,parts :herein described and claimed.

=Generallythereis:providedan apparatus which is associated with each:wheel of a vehicle equipped with pneumatic tires and which sapiparatus-is motivated by the pressure contained in its associated tire toindicate ithrough .-novel electrical switches, :contacts .and circuits.by :meanspf signal :lights orother means convenient to the operatorwhether the particular tireis at normal pressure or whether such tirecontains 'toorgreat :or too ilittleair pressure.

It is accordingly an object of .the invention to .provide an apparatusof the character set forth which is comparatively :simple inconstruction, automatic in its operation andyet effective and efiicientin use.

Another object of the invention :is, to provide an apparatus ofthe-.character'set forth which will automatically signal to a vehicleoperator the pressure condition .of :each of the tires of such vehicle.

A further object of the invention is to provide, in .-a device of thecharacter set forth, a novel electrical switch forminga apart of theinvention.

A still "further object of the invention. is the provision of a novelelectrical contact :member iorminga part ofthe invention.

Other and further objects of the invention .will

:become apparent :from a reading of the follow- .ing specification takenin conjunction with the drawings, in which:

Figure 1 is a side elevational'view-of an embodiment of the invention,

Figure .2 is a sectional view taken along line 2-,2'of Figure 1,

Eigur 3 is a fragmentary sectional view taken along li-ne.3--.3 ofFigure .1,

Figure 4 is .a sectional view taken along line 4-4 of Figure 2 in thedirection of the arrows,

Figure 5 is a sectional view likewise takemalong line of Figure 52 hutin the direction opposite to the arrows,

Figure 6 is a fragmentary plan view of an -electrical contact,

Figure 7 is a sectional view taken along line l-l ofFigure 5,

Figure '8 is an enlarged fragmentary elevational view of the apparatusshown in Figure 1,

"Figure 9 is a fragmentary sectional view' taken along line99 ofFigure8, and

Figure 10 is a schematic view illustrating the electrical circuitsinvolved with one of the tires 2 which circuits form .a part of thepresent invention.

Referring :more particularly to the drawings, there is shown therein awheel 9 provided with :a tire ill, a wheel disc 11, brake drum [2provided.- with a :cover plate 13 and a wheel spindle 14.

.A disc 215 of dielectric :material is affixed in any suitable mannerabout the "brakes [6 carried withinitheibralredrum 1:2 'andmounted uponthe outer face :of the disc 15 is.a seriesof three concentricrings .l 1,18 and .19 of electrically conductive material. .Afiixed :to the outerface :of the wheel i9 is a vframework 1213 preferably and shown formedof wire and which is .aflixe'd to the wheel ".3 .by meam of clamps-2:!'or the like.

lviounted upon the frame 20 by means of a bracket 2-2 is a cylinder 23provided at :one entl with a-fitting 24 which connects with a tube ;25of flexible :material :and which tube, in turn, is connected with afitting 125 :on the tire 1.0.

-A piston 12'! isslidably mounted within the cylinder -2-3 and hasconnected thereto an outwardly extending rod 28. Within the cylinder .23there is ,providedan exp'ansiblebulb 29 formed .of rubber or otherflexible material and connected at its open end with the fitting 24, asindicated at .Sll, and having its closed end hearing against the ,piston21. A compression-spring .34! :surrounds the rod 28 and bears againstthe .outer .end of thecylinder 2-3.

A vertically ext-ending plate 32 is aifixed to .the frame?!) (and :has:pivotally connected therewith, .as indicated at '33., .34 :and 35,contact actu- .ating arms .35, :3! and 38, respectively. Aflix-ed totheplate 32 inwardlyofthe'arms 36, Hand 38 is a .series of springs offiat metal 39, 40 and 41 :each :of which is respectively provided withan rout-turned :guide member 42, 43 and 44, which ,guide rmemberssurround, respectively, the arms 36, 3-1 and 38. The springs .39, 49 and4! individually act to normally hold their associated arms 36, 3 and .38outwardly from the wheel 9.

The-outer :ends of each of the arms 36,, .31 and .38 extend through ahead 45 affixed to a block 46 of insulative material to which, in turn,is connected .a stem 4? which extends inwardly through :a collar 48laterally mounted 'in the wheel 9..

The inner end of the stem 41 is jprovided with .a yoke 49 whose legscarry an axle '55 upon which i mounted -a roller 5!. Each of the rollers5| is adapted, when moved inwardly by its respective arm 36, 31 or 38 tocome into rolling contact with one of the contact rings l1, H3 or [9.

The outer end of the rod 28 is connected by means of a line 52 with anarm 53 aflixed to and extending outwardly from a shaft 54 which extendssubstantially in a direction parallel to the sides of the plate 32 andwhich is pivotally mounted upon the frame 29 by means of brackets 55 and59. The shaft is provided with a crank 5'! having buffer members 58 and58a mounted thereon and a crank 59 upon which is mounted a pair ofbuffer members 69 and 6 I The contact ring I9 is connected by means of awire '62 to a lamp 63 mounted in a panel 64 carried at a pointconvenient to the operator of the vehicle upon which the presentapparatus is attached as, for example, a dashboard 65. The lamp 63 is inturn, connected by a wire 63 to a source of electrical energy as, forexample, a vehicle battery El. The contact ring I8 is connected by awire 12 to the battery 61. The contact ring I! is connected by a wire Hto the lamp 59 and a Wire T9 interconnects the lamp 69 and the battery61.

In operation, it will be apparent that in the event the tire 19 shouldcontain an air pressure below that required for proper operation, thatthe bulb 29 will shrink in size thereby allowing the spring 31 to movethe piston 21 inwardly of the cylinder 23 thus moving the rod 28likewise in an inward direction. This action causes the link 52 and thearm 53 to turn the shaft 54 in a counterclockwise direction, as viewedin Figure 9 of the drawings, thus moving the crank 51 outwardly and awayfrom the arm 36 while at the same time causing the crank 59 to moveinwardly whereupon the buffers 59 and 9| will cause the arms 37 and 38to move inwardly against the action of the spring 49 and 4| and tothereby carry their respective rollers 5| inwardly into contact with therings 18 and 19 to thus complete an electrical circuit which includesthe lamp 63, the stems 41 of the contacting rollers, the collars 48 ofsuch stems, the wheel 9, the wires 62, 66 and 12, and the battery 61.The lamp 63 has indicia 13 imposed upon the panel 64 adjacent thereto,which indicia indicates to the operator, when the lamp 63 is lighted,that the pressure in the tire i is dangerously low.

On the other hand, if the air pressure within the tire I9 becomes toogreat for safe operation of the vehicle, the bulb 29 will be expanded tothereby move the piston 21 outwardly in the cylinder 23 against theaction of the spring 3| to thereby, through the rod 28, link 52 and arm53, cause a clockwise movement of the shaft 54 to thus cause the buffermembers 58 and 58a to impinge against the arms 36 and 31 against theaction of the spring 39 and 40 while at the same time releasing thepressure of the buffers 69 and 6! against the arms 3'! and 38 and thusallowing the spring 41 to move the arm 38 outwardly with respect to thewheel 9. Such action causes the roller associated with the arm 38 tomove out of contact with the ring l9 while causing the rollers 51 and 31to come into contact with the contact rings I1 and i8 to therebycomplete an electrical circuit which includes the lamp 69, the stems 41of the contacting rollers, the collar 48 of such stems, the wheel 9, thewires 79, H and 12, and battery 67. The panel 64 bears indicia 14adjacent the lamp 69 to indicate, when the lamp 69 is lighted, that thepressure in the tire I0 is too great. It will be understood that whilebut one wheel and its associated electrical circuits has been shown anddescribed herein that obviously the identical apparatus and circuits maybe utilized for each of the wheels of a vehicle and that the panel 64may contain lamps associated with such additional wheels together withsuitable indicia to indicate the condition of air pressure within eachof the tires of the vehicle.

It will also be seen that the cranks 51 and 59 lie in the same plane andthat when such plane is in parallel relation to the plane of the wheel9, that none of the bufiers 58, 58a, 60 and BI will bear against any ofthe arms 36, 31 and 38 and that in such condition neither of the lamp 63and 69 will be lighted. Obviously in such condition the air pressurewithin the tire i9 is at its proper lever and the piston 21 is in aposition between its innermost position caused by a shrinking of thebulb 29 and its outermost position caused by a swelling of the bulb 29.

While but one form of the invention has been shown and described herein,it will be readily apparent to those skilled in the art that many minormodifications may be made without departing from the spirit of theinvention or the scope of the appended claim.

What is claimed is:

A switch for use with a pneumatic tired wheel of an automobilecomprising an air pressure responsive device mounted upon the wheel forrotation therewith, a brake drum and a brake mechanism associatedtherewith, a disc of dielectric material afiixed upon said brakemechanism concentrically with said drum, three concentric contact ringsmounted upon said disc, three reciprocal contact members extendingthrough said drum and each adapted to contact one of said rings whenmoved inwardly of said wheel, pressure-operated means connected withsaid pressure responsive device forrselectively moving said reciprocalcontact members to contact the center and outer or the center and innerrings, said rings, and said contact members, said pressure reciprocaldevice including a cylinder, a piston within the cylinder, a piston rodconnected to said piston at its inner end and extending outwardly fromsaid cylinder, a shaft, an arm extending radially from said shaft andpivotally connected with the outer end of the piston rod, and meansincluding said shaft for selectively reciprocating said contact members,said last mentioned means including a plate carried on the outer side ofthe wheel, arms hingedly connected at one end with said plate andextending through the outer ends of the contact members, springs forurging said arms outwardly of said wheels, and a pair of oppositelyextending cranks formed in said shaft and lying in the same plane witheach other, each of said cranks adapted to bear against selected pairsof said arms to thereby move the contact members inwardly when saidshaft is rotated by the movements of the piston.

LUMPKIN D. LOGGINS.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,599,846 Sinclair et al Sept. 14, 1926 2,113,474 Edmonston etal. Apr. 5, 1938 2,283,601 Erickson May 19, 1942 2,481,864 Peck Sept.13, 1949

